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Discussion Starter #1
Hello,

I have a 2008 Sportsman 800 and over the last year it has been giving me really hard starts regardless of the temp outside. Colder weather is much worse but today was 92 outside and still giving me issues It has progressively got worse over the last year. When I bought it there was no issues.. I've changed the air filter, oil, plugs, cleaned the maf, new battery (fully charged) but still running into issues. It will take 2-4 times of starting it before it will idle and sometimes will die during idle. Once it is up and running it runs good and has no issues. If I stop it and start it back up it will start fine. Once it cools down starting issues happen again.

I've uploaded a video to show the issue it's having. Any help is greatly appreciated.

 

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19’ 850SP Camo. MtAiry Maryland
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Since it runs and starts fine when warm, it might be the valve lash out of adjustment. -just a thought-
 

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19’ 850SP Camo. MtAiry Maryland
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Sounds like good preparation, there will likely be others here that might suggest checking other stuff first, but if the valves have never been adjusted they may need it.
 

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The valve lash is hydraulic
142678

So it becomes compression, ignition and fuel as the likely suspects. Which one of the three is not up to standards.
 

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Discussion Starter #7 (Edited)
I don't know if the fuel filter has ever been changed. I just got the service manual so gotta figure out where it is. I'll check the grounds as well as that is easy to do. I have a compression tester for my 71 firebird so maybe that will work and I can test compression as well.

Unsure how to test spark though.

Edit: found a thread on how to check spark. I'll dig into this shortly.
 

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Discussion Starter #9
It isn't burning oil at all. I changed the oil a few months ago and maybe put 15-20hrs on it since the next change. Still full and clean when I changed it out. I'm going to test the compression tomorrow.
 

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Sounds like good preparation, there will likely be others here that might suggest checking other stuff first, but if the valves have never been adjusted they may need it.
My 900rzr started like that and eventually wouldn't start at all. Thought it was the top end cause of low compression!! Bought a top end kit. When I took it apart. Noticed the Hydraulic cam chain tensioner had FAILED!!! Loosening the chain and sprockets out of timing. And sprockets were a bit rounded.
Not sure if go back with mechanical or OG hydraulic.
 

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clean your carb, adjust freeplay.
pull your spark plug and see how it looks,

feather the throttle as you start it, does it start right away? if so, clean your carb,
 

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clean your carb, adjust freeplay.
pull your spark plug and see how it looks,

feather the throttle as you start it, does it start right away? if so, clean your carb,
A 2008 800 is EFI so no carb. It may indeed need the TB cleaned. Most 800's do with age.
I'm betting on low compression from either worn rings and/or leaking valves needing worked on...
Or more likely, all of the above.
 

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Discussion Starter #13
Sorry for the late response. I haven't had a chance to get to compression testing it yet. Work has been kicking my ass the last few weeks. I'll be testing that this weekend if not tomorrow night.
 

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Discussion Starter #14 (Edited)
Compression testing done. 150 on both sides on the dot. I did notice that the air breather on the engine was totally loose. About 1/8" gap. Cleaned that up and tightened it down. Wires look good but I have not tested them with an OHM meter or tested the ignition coils.

EDIT:
Checking ohms and not getting any readings at all with or without the plug wires connected. I know the meter works, I ohm'd one of my speakers and for 4.2 for a 4ohm speaker. So guessing the ignition coil is shot at this point?

Checked the wires off the coil, A wire is 4.95, B wire is 2.96.
 

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Discussion Starter #15
New wires and coil, still has starting issues. Runs a lot better though once it gets going.
 
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